The Georgia Tech-SAIC Sting Racing Team has been informed that we were among a set of participants that did not advance to the Urban Challenge finals on November 3rd. As a first-time entrant, the team has done an outstanding job making it to the semi-final round of the world’s most challenging robotics competition. We wish to express our gratitude for all the support we have received from Georgia Tech and the Atlanta community, as well as the expertise and technical support from our industry teammate, SAIC. We also give a hats-off to DARPA for administering a fair and flexible race.

Looking forward, we are excited to continue our part in the evolution of autonomous robotics research and the development of intelligent, safe vehicles. Our efforts in the DARPA Urban Challenge – particularly our autonomous vehicle, Sting 1 – will play a key role in our future research agenda, particularly as we study the safety and viability of implementing robotic elements on the road and in the home. We will remain here in California to root for the remaining competitors and learn all we can for next time.

Last night we were informed by DARPA that Sting 1 will not be able to qualify for the finals. They requested that our race slots be used for teams that might make the race. Obviously we agreed on the schedule changes to accommodate teams that might make the finals.

It has been a race with some serious challenges after the crash last Saturday. We have worked hard to rectify the problems and to address the unforeseen problems that we have encountered. Unfortunately it was not enough.

The team is obviously very disappointed. We have worked hard to get to the race and have a truly amazing platform. We are now going to watch the rest of the qualifiers and the finals to learn as much as possible. In addition the team will take it easy a few days to recover from weeks of long hours.

We’re very happy with our run on Course C today. In this course the vehicle runs loop after loop in a housing area, and other cars (driven by stunt drivers) interact with it at four-way stops. The robot got stuck once, requiring an intervention — our lead programmer had to restart one of our processes. We’re still assessing the cause of the problem. But overall the vehicle behaved very nicely.

Tomorrow morning we’re back on in Course A. This is the one that is grinding up lots of cars — besides our accident, there have been several others there. We’ve been investing a lot of time tuning our code for that test.

In our Saturday afternoon test in Area A Sting 1 crashed head-on into a concrete barrier. The front sensor mount was bent severely and pushed into the front of the vehicle. Fortunately the protection offered by the design and strength of the sensor mount saved the sensors.

After assessing the log data we determined the cause of the accident was a failure in the communication link between our GPS/IMU and the main control computer. Without “pose” information the robot could not know that it was moving.

Recovery: Tartan Racing helps out

Our first order of business after the accident was to assess the damage and develop a plan, and we needed to fix the problem that caused the accident in the first place. The GM mechanics with Tartan Racing (CMU & GM) came well equipped to the site, and were eager to help us out. With their help we cut the main sensor mounting plate out, bent the metal back into alignment and welded everything back in place.

We give a big THANK YOU to GM and Tartan Racing!

The loss of comms between the GPS and the control computer could have occurred in several places, including the computer’s hardware, the linux serial drivers, or our code. We have circumvented the first two possibilities by installing a serial to USB converter and we access the GPS via USB. On the software side we added checks to make sure that pose information is streaming in, otherwise the robot brakes and reboots the computer.